servers/is/main.c

   1 /* System Information Service.
   2  * This service handles the various debugging dumps, such as the process
   3  * table, so that these no longer directly touch kernel memory. Instead, the
   4  * system task is asked to copy some table in local memory.
   5  *
   6  * Created:
   7  *   Apr 29, 2004       by Jorrit N. Herder
   8  */
   9
  10 #include "inc.h"
  11 #include <minix/endpoint.h>
  12
  13 /* Allocate space for the global variables. */
  14 message m_in;           /* the input message itself */
  15 message m_out;          /* the output message used for reply */
  16 int who_e;              /* caller's proc number */
  17 int callnr;             /* system call number */
  18
  19 extern int errno;       /* error number set by system library */
  20
  21 /* Declare some local functions. */
  22 FORWARD _PROTOTYPE(void sig_handler, (void)                             );
  23 FORWARD _PROTOTYPE(void get_work, (void)                                );
  24 FORWARD _PROTOTYPE(void reply, (int whom, int result)                   );
  25
  26 /* SEF functions and variables. */
  27 FORWARD _PROTOTYPE( void sef_local_startup, (void) );
  28 FORWARD _PROTOTYPE( int sef_cb_init_fresh, (int type, sef_init_info_t *info) );
  29
  30 /*===========================================================================*
  31  *                              main                                         *
  32  *===========================================================================*/
  33 PUBLIC int main(int argc, char **argv)
  34 {
  35 /* This is the main routine of this service. The main loop consists of
  36  * three major activities: getting new work, processing the work, and
  37  * sending the reply. The loop never terminates, unless a panic occurs.
  38  */
  39   int result;
  40   sigset_t sigset;
  41
  42   /* SEF local startup. */
  43   env_setargs(argc, argv);
  44   sef_local_startup();
  45
  46   /* Main loop - get work and do it, forever. */
  47   while (TRUE) {
  48       /* Wait for incoming message, sets 'callnr' and 'who'. */
  49       get_work();
  50
  51       if (is_notify(callnr)) {
  52               switch (_ENDPOINT_P(who_e)) {
  53                       case SYSTEM:
  54                               printf("got message from SYSTEM\n");
  55                               sigset = m_in.NOTIFY_ARG;
  56                               for ( result=0; result< _NSIG; result++) {
  57                                       if (sigismember(&sigset, result))
  58                                               printf("signal %d found\n", result);
  59                               }
  60                               continue;
  61                       case PM_PROC_NR:
  62                               sig_handler();
  63                               continue;
  64                       case TTY_PROC_NR:
  65                               result = do_fkey_pressed(&m_in);
  66                               break;
  67                       default:
  68                               /* FIXME: error message. */
  69                               result = EDONTREPLY;
  70                               break;
  71               }
  72       }
  73       else {
  74           printf("IS: warning, got illegal request %d from %d\n",
  75                 callnr, m_in.m_source);
  76           result = EDONTREPLY;
  77       }
  78
  79       /* Finally send reply message, unless disabled. */
  80       if (result != EDONTREPLY) {
  81           reply(who_e, result);
  82       }
  83   }
  84   return(OK);                           /* shouldn't come here */
  85 }
  86
  87 /*===========================================================================*
  88  *                             sef_local_startup                             *
  89  *===========================================================================*/
  90 PRIVATE void sef_local_startup()
  91 {
  92   /* Register init callbacks. */
  93   sef_setcb_init_fresh(sef_cb_init_fresh);
  94   sef_setcb_init_lu(sef_cb_init_fresh);
  95   sef_setcb_init_restart(sef_cb_init_fresh);
  96
  97   /* Register live update callbacks. */
  98   sef_setcb_lu_prepare(sef_cb_lu_prepare_always_ready);
  99   sef_setcb_lu_state_isvalid(sef_cb_lu_state_isvalid_standard);
 100
 101   /* Let SEF perform startup. */
 102   sef_startup();
 103 }
 104
 105 /*===========================================================================*
 106  *                          sef_cb_init_fresh                                *
 107  *===========================================================================*/
 108 PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
 109 {
 110 /* Initialize the information server. */
 111   struct sigaction sigact;
 112
 113   /* Install signal handler. Ask PM to transform signal into message. */
 114   sigact.sa_handler = SIG_MESS;
 115   sigact.sa_mask = ~0;                  /* block all other signals */
 116   sigact.sa_flags = 0;                  /* default behaviour */
 117   if (sigaction(SIGTERM, &sigact, NULL) < 0)
 118       report("IS","warning, sigaction() failed", errno);
 119
 120   /* Set key mappings. */
 121   map_unmap_fkeys(TRUE /*map*/);
 122
 123   return(OK);
 124 }
 125
 126 /*===========================================================================*
 127  *                              sig_handler                                  *
 128  *===========================================================================*/
 129 PRIVATE void sig_handler()
 130 {
 131   sigset_t sigset;
 132
 133   /* Try to obtain signal set from PM. */
 134   if (getsigset(&sigset) != 0) return;
 135
 136   /* Only check for termination signal. */
 137   if (!sigismember(&sigset, SIGTERM)) return;
 138
 139   /* Shutting down. Unset key mappings, and quit. */
 140   map_unmap_fkeys(FALSE /*map*/);
 141
 142   exit(0);
 143 }
 144
 145 /*===========================================================================*
 146  *                              get_work                                     *
 147  *===========================================================================*/
 148 PRIVATE void get_work()
 149 {
 150     int status = 0;
 151     status = sef_receive(ANY, &m_in);   /* this blocks until message arrives */
 152     if (OK != status)
 153         panic("IS","sef_receive failed!", status);
 154     who_e = m_in.m_source;        /* message arrived! set sender */
 155     callnr = m_in.m_type;       /* set function call number */
 156 }
 157
 158 /*===========================================================================*
 159  *                              reply                                        *
 160  *===========================================================================*/
 161 PRIVATE void reply(who, result)
 162 int who;                                /* destination */
 163 int result;                             /* report result to replyee */
 164 {
 165     int send_status;
 166     m_out.m_type = result;              /* build reply message */
 167     send_status = send(who, &m_out);    /* send the message */
 168     if (OK != send_status)
 169         panic("IS", "unable to send reply!", send_status);
 170 }
 171
 172